1. Field of the Invention
The present invention relates to a compensated tool holder for tapping spindles.
More particularly, the present invention relates to a compensated tool holder for tapping spindles especially suitable for machine tools.
2. Description of the Prior Art
As known, the tapping spindles of the known art includes an external am body and an internal body (xe2x80x9ctool holderxe2x80x9d), coaxially associated.
The main body has an external conic conformation suitable to be coupled and tied, by a ring nut, to the corresponding conic seat of the standardized attachments or spindles for tool machines, and comprises an internal chamber wherein the internal body (xe2x80x9ctool holderxe2x80x9d), with the related dampening intermediate spiral spring, is coaxially located.
The rotationally drawing of the internal body is obtained through the coupling of its lower end having a polygonal peripheral profile with a corresponding polygonal hole of the main external body.
The internal body (xe2x80x9ctool holderxe2x80x9d) comprises a cylindrical coaxial through-seat, and it is provided with radial threaded holes arranged in its upper part. In said seat, the tang of the male tools engages and it is fastened, for the rotational drawing, through threaded dowels coupled to said radial threaded holes. The main drawback of the known tapping spindles is the creeping friction of the polygonal coupling between the internal body (xe2x80x9ctool holderxe2x80x9d) and the external body does not allow a regular dampening.
Moreover, the replacement of a screw tap is an operation rather laborious and involve a remarkable loss of time. In fact, it requires: the unscrewing of the fixing ring nut, the disassembly of the spindle from the conic seat of the machine attachment, the loosening of the locking dowels of the male tang to the internal body, the replacement of the screw tap, the locking of the dowels, the re-assembly of the spindle in the attachment, the screwing of the ring nut.
Another drawback of the known tapping spindles is that the spindle does not comprise any protection rings that could allow to prevent the internal dirtying due to greases and/or powders.
Object of the present invention is to eliminate the above drawbacks.
More particularly, an object of the present invention is to provide a compensated tool holder for tapping spindles of simple and easy construction and use and low cost.
A further object of the present invention is to provide a compensated tool holder for tapping spindles such as to allow the rapid replacement of tapping tools without needing to be dissemble from the operating heads.
Still another object of the present invention is to provide a compensated tool holder for tapping spindles suitable to be used with any type of standardized attachment, with profiles of any unified type.
According to the resent invention, these and still other objects that will become clear thanks to the following description, are achieved by a compensated tool holder for tapping spindles constituted of a central coaxial body with a concentric stem seat comprising an upper hollow half-pin and a lower hollow half-pin that engage mutually and coaxially through a semielastic conic coupling and a sequential threaded coupling, associated with each other.
The conic coupling is constituted of a continuous conic seat located on one of said hollow half-pins, which can slide axially, under the action produced by a threaded coupling, on a complementary conic male part, discontinuous and elastically deformable, that squeezes on the stem of the tools to be tapped, tying the same.
The general structure of the spindle and the configuration of its details are very simple, elementary and of easy construction, just as is simple the manner of use of said spindle.
Besides, the compensated tool holder for tapping spindles of the present invention allows a rapid replacement of the tapping tools, without needing to disassemble them from the operating heads, but acting directly on the direct opening and closing of the tool holder.